1. Field of the Invention
This invention relates to the field of tip-out sashes, namely window sashes and the like which are alternatively slidable in a jamb and rotatable out of the plane of the jamb. More particularly the invention relates to such a device wherein an automatically-deployed retaining apparatus on the tip-out sash fixes a free edge of the sash to the jamb when the edge is spaced from the jamb, until fully released by positive action of the user.
2. Prior Art
Tip-out sashes are known wherein overlapping sashes (i.e., movable panels) of a window, door or the like, which normally slide up and down (or back and forth) over one another in complementary inward-facing grooves of a jamb (e.g., window frame), are arranged such that the sash is fixed in the grooves of the jamb only at upper and lower lateral fixing pins, usually at the corners of the sash. At least one edge of the sash can be released from the jamb by linearly retracting the lateral fixing pins or other fixing means at said corners. In that event, the sash is fixed to the jamb only at the remaining lateral fixing pins and can be rotated out of the plane of the jamb around an axis defined said remaining lateral pins. Normally the pins at the upper edge are retracted, allowing the sash to rotate inwardly around the pins at the bottom edge.
Resiliently-mounted tenons can be provided as the fixing pins at the removable edge of the sash. Fixed pins can be provided at the pivot edge, the tenons and fixed pins fitting into the channels facing inwardly along either side of the jamb. Typically, a spring biased manually retractable tenon is provided at each of the two opposite lateral corners of the sash at an upper edge, and at the lower edge fixed rotary pins or sliding fittings define the pivoting axis when the sash is released from the jamb.
Tip-out sashes are useful to facilitate washing the glass on the outer face of the sash while remaining inside the building. Tipping the sash inwardly of the window turns the outer face of the window upward for easy cleaning, thereby avoiding the inconvenience of scaffolds, ladders, etc.
It is possible to locate a fixed pin midway along each lateral side of the sash, with retractable tenons at the top and/or bottom. Such a device is difficult to operate if retractable pins are provided at top and bottom, and is not secure if either is omitted. A person who operates a tip-out sash with the retractable tenon at the top and fixed pin at the bottom, however, must support the weight of the sash when the releasable edge of the sash is disengaged from the jamb. As a function of the cosine of the angle at which the sash is tipped, a greater or lesser proportion of the weight of the entire sash must be borne by the user. When tipped fully horizontally, the user must support nearly the entire weight of the sash. At times, a user will miscalculate the weight of the sash when tipping it out, particularly with multi-pane thermal sashes, counterbalanced sashes, etc., and the user may have difficulty in controlling the sash due to its unexpected weight. In that case, the sash can be dropped, with damage to the sash and possible injury to the user.
Any lack of control of a tip-out sash of course is aggravated in larger windows as compared to smaller ones. In addition to the problem of a user underestimating the sash weight, there is a problem that the weight load of the sash may deform the jamb. The weight of the upper sash is supported by the window frame or jamb when the sash is fixed in place. There is then a tendency for the two vertical members defining the sides of the jamb to bow outwardly. This outward bow defines its maximum clearance with the sash at a midpoint between the top and bottom of the jamb, the midpoint unfortunately corresponding to the locations of the retractable tenons or fixed pins of the sashes. In a sufficiently large window, without adequate support, outward lateral bowing of the jamb may cause an edge of a tip-out sash to be released from the jamb and dropped, especially with other loads occurring on the building, such as settling, wind action, etc. In case of a large jamb or with people nearby, such a release can cause severe damage.
According to the present invention, an automatically deployed linkage is provided to hook the free edge of the sash to the jamb at a preliminary position when the tip-out means is operated to allow the sash to be tipped. The linkage is deployed by the weight of the sash but is spring biased to remain folded and stowed along the sash edge until the sash is tipped out. The linkage automatically collapses for stowage against the edge of the jamb when unhooked from the jamb, which requires a deliberate manual action by the user. The distal end of the linkage defines a hook to engage the window frame or jamb at any point along the vertical traverse of the sash in the jamb, avoiding the possibility of inadvertently dropping the sash from the jamb unless the user intentionally releases the sash from the limited tip displacement at which it is retained.
Means for limiting the extent of pivoted displacement of a window-panel in a jamb are known in casement-type windows. U.S. Pat. No. 4,691,950-Mayer et al discloses a rigid one piece connecting bar which is pivoted by one end at the vertically-hinged window panel, and engages by an opposite end in an open ended slot fixed to the window jamb, which slot normally keeps the connecting bar captive by said opposite end thereof. The connecting bar can be released from the open ended slot when the window is closed by displacing the connecting bar against spring pressure such that the opposite end moves clear of the open ended slot. This must be done when first opening the casement window. In this manner, the window can be fixed part way open as defined by the connecting bar, or allowed to open completely. The connecting bar can only be manipulated into and out of the open ended slot when the window panel is pivoted closed, because the connecting bar is a rigid link element and is arranged such that the connecting bar barely has sufficient length to clear the slot when the sash is fully closed.
A stop for a pivoting window panel is also disclosed in U.S. Pat. No. 4,620,393-Stafset. In this device, a latch member can be placed over a retaining pin or released at the user's option, the latch member defining a fixed part way open position of the pivoting window panel.
With pivotally mounted window panels (i.e., casement windows), it is quite common to have not only a means for fixing the movable window panel at a particular angular displacement from the window jamb, but also to make this fixing means adjustable in length. U.S. Pat. No. 4,605,252-Yamamoto, for example, allows the user to manually position the vertically-hinged casement panel as required, and then to fix the panel at that position via an adjustably extendible connecting arm, telescoped to allow angular displacement of the window panel, and fixable at any of a plurality of different extensions at the user's option.
None of the foregoing references provides a means for fixing a tip-out sash, such that the sash slides normally, tips out when and where desired, and can only tip-out to the limited predetermined displacement unless the fixing means is first fully released by deliberate action of the user. Such an arrangement would seem to be inherently precluded because if the sash is to be movable there can be no means fixed in position on the jamb for receiving an end of a retaining bar.
A connecting member for fixing the maximum displacement of two pivotably displaced members is not readily attached to a sash or jamb which are slidably displaced, because any connecting member can be expected to interfere with operation of the sash in the sliding mode. In short, means fixing a maximum pivoted displacement of a sash are likely to interfere with sliding and means facilitating sliding are difficult to envision where the sliding structures are more complicated than pins in slots, e.g. a pin at each of the four corners of a sash, one pair of oppositely-directed pins being retractable to allow pivoting around an axis defined by the other pair of pins.
According to the invention, the foregoing conflicts are resolved without the expected drawbacks of a connecting arm between a sash and jamb. The invention enables sliding of the sash without interference, tipping of the sash at any point along its slide path, in an at least temporary releasable linkage defining a maximum extent of deflection of the sash from the jamb.